The Federal Reserve may now understand what you and I and everyone who works for a living already knows — the US economy is a lot weaker than Washington has been pretending it is.

The Fed’s Open Market Committee on Wednesday decided not to cut back on the securities purchases it is making through its quantitative easing program. Wall Street had widely expected those purchases to be reduced from the current $85 billion a month to $75 billion, or less.

The reason there was no cut? Chairman Ben Bernanke said the committee — in a strong 9-to-1 vote — felt the US economy couldn’t handle less help from the Fed.

This is a very complicated issue, and I’d have to put a hard cover around this column and call it a book to get to everything. But I’ll give you the condensed version, starting with a prediction I made in a column that was published June 20.

Back then, Bernanke had just started talking about cutting back QE — or “tapering” as Wall Street calls it — and suggested that the controversial program could even end altogether by the middle of next year.

To that idea I said on June 20: “The trouble is the economy isn’t really doing what Bernanke thinks it is. So don’t be surprised in the next couple of months if there’s an about-face and all this QE retirement talk is, well, retired.”

Surprise! I was right.

First, let me explain some of the terms for those of you who can’t keep up with all this financial nonsense because you are too busy trying to put food on the table.

Quantitative easing is nothing more than a fancy term for printing money.

Starting in late 2008, the Fed began “printing” trillions in additional dollars that would be used to purchase Treasury bonds in order to keep interest rates low and — it hoped — help the economy grow.

Later the Fed added mortgage securities to its purchases, and the total amount eventually grew to the $85 billion-a-month figure.

This isn’t money in the traditional sense of the word. It’s digital money — numbers on the Fed’s balance sheet. And this digital money was good for one thing: purchasing securities in the financial markets.

So the Fed was (and is), in essence, using fake money — about $3.66 trillion so far — to purchase bonds and mortgages that others would have to purchase with real money.

Bernanke’s intentions started out honorably.

When the US banking sector was in trouble five years ago, liquidity — meaning lots of money — was needed to make sure the wheels of commerce and finance were greased.

A second purpose for QE was to keep interest rates so low that businesses would want to take out loans and expand, and consumers would want to borrow and spend.

By then the Fed had already pushed interest rates down to near zero with traditional policy — which essentially consists of demanding that borrowing costs go down. So, as a last resort, QE was tried.

And rates have stayed low — at least until last May.

The problem, however, is that these lower borrowing costs haven’t translated into a healthy economy.

“Conditions in the job market today are still far from what all of us would like to see,” Bernanke said at a Wednesday afternoon press conference.

But even that moderate growth is an illusion.

As I’ve been explaining, the government’s economic statistics are deceiving us. That’s why I made that June 20 prediction.

The most important figures that come out of Washington have always come with the monthly employment report. And because of the way the Labor Department constructs those numbers, they always look abnormally good in the spring and weaker in summer.

Always!

This summer was no different. August’s job gains were disappointing — not even robust enough to absorb all the people looking for their first job.

But the real shocker in the last Labor report was that the moderate job increases originally reported for June and July didn’t hold up — they were lowered substantially.

The Fed probably doesn’t even know this yet but the September employment report (to be released on Oct. 4) could be an especially big stinker.

The Fed is a lot smarter than I am, so I’m sure Bernanke and his Ph.D.s have other figures that show the risks that the economy is facing.

Yes, new car sales are up sharply — but only because of huge lease incentives. And, true, housing purchases have risen — but largely because large investors have taken a shine to real estate at a time when other assets look dull.

After expecting the worst, the stock and bond markets yesterday cheered the Fed’s decision not to cut back on QE. The Dow Jones industrial average and S&P 500 rose to record levels, gold jumped 4.2 percent to $1,366.25 an ounce, oil rose more than 2.5 percent, and the yield on the 10-year fell to 2.71 percent.

But that decline will be only temporary. It’s still above the 1.9 percent lows of May, and the Fed has shown it is increasingly powerless to do anything about them.

So where does the non-taper leave us?

I’ll tell you. It leaves us with a Wall Street hopelessly addicted to cheap money, an economy and jobs market unable to be jump-started and with plenty of potential mines down the road.

One land mine is the upcoming debt-ceiling talks.

I have another prediction to make today: if Congress and President Obama cause enough tension over debt ceilings and deficits in the months ahead, the situation in the financial markets will get more exciting than either you or I want.